What might inventor A do if a recently granted patent to person B was, in all its details, the same as something A previously invented well before B's filing and could prove the complete history of ...

Let's imagine a patent is filed in 2003 and later approved by the USPTO. Let's imagine someone wants to challenge it with valid prior art (year 2000 for example).
Which legislation applies? The one ...

In the past I've been discouraged from filing provisional applications (in the US), but the new "first to file" provisions of the "America Invents Act" would seem to make a provisional application a ...